import sequtils,strutils,strscans,math

type
    priorityQue[I:static[int];T:tuple] = array[I + 1,T]
    item = tuple[p : int,cost : float64, weight : float64, bitflag : int]
proc push[T](A:var priorityQue; b: T)=
    const key = 1
    A[0][0] += 1
    A[A[0][0]] = b # A[0][0]はsize、最大のIndex
    var index = A[0][0]
    while index > 1 and A[index][key] > A[index div 2][key]:
        (A[index],A[index div 2]) = (A[index div 2],A[index])
        index = index div 2
proc pop(A: var priorityQue):item =
    const key = 1
    result = A[1]
    A[1] = A[A[0][0]]
    var a : item
    A[A[0][0]] = a
    A[0][0] -= 1
    var index = 1
    while index * 2 <= A[0][0]:
        if index * 2 + 1<= A[0][0]:
            if A[index][key] < A[index * 2][key] and A[index * 2 + 1][key] <= A[index * 2][key]:
                (A[index],A[index * 2]) = (A[index * 2],A[index])
                index = index * 2
            elif A[index][key] < A[index * 2 + 1][key]:
                (A[index],A[index * 2 + 1]) = (A[index * 2 + 1],A[index])
                index = index * 2 + 1
            else:
                break
        elif index * 2 <= A[0][0]:
            if A[index][key] < A[index * 2][key]:
                (A[index],A[index * 2]) = (A[index * 2],A[index])
            break
        else:
            break
proc size(A : priorityQue):int=
    return A[0][0]

type
    zahyou = tuple[x : int, y : int, w : float64]
var
    ax,ay,x,y : int
    w,SW : float64
    N : int
    s : string
    mintime : array[15, array[1 shl 14, float64]]
    PQ : priorityQue[500000, item]
(ax, ay) = stdin.readline.split.map(parseInt)
N = stdin.readline.parseInt
var tizu = newSeq[zahyou](N + 1)
for n in 1..N:
    s = stdin.readline
    discard scanf(s,"$i $i $f",x, y, w)
    tizu[n] = (x - ax, y - ay, w)
    SW += w
var
    t,t2 : item
    p,p2 : zahyou
t = (0, 0.0, SW, 1)
PQ.push(t)


while PQ.size > 0:
    t = PQ.pop()
    var
        b = t.bitflag
        T : float64 = (t.weight + 100) / 120
    for k in 1..N:
        if ((1 shl k) and b) == 0:
            p2 = tizu[k]
            p = tizu[t.p]
            var d = (abs(p2.x - p.x) + abs(p2.y - p.y)).float64
            t2 = (k, t.cost - T * d - p2.w , t.weight - p2.w, b or (1 shl k))
            if countBits32(t2.bitflag.int32) == N + 1:
                t2.cost -= (abs(p2.x) + abs(p2.y)).float64 * (100 / 120)
            if mintime[k][t2.bitflag] == 0 or mintime[k][t2.bitflag] < t2.cost:
                mintime[k][t2.bitflag] = t2.cost
                PQ.push(t2)

var ans : float64 = Inf
for i in 1..N:
    if mintime[i][(1 shl (N + 1)) - 1] == 0:
        continue
    ans = min(ans, - mintime[i][(1 shl (N + 1)) - 1])
echo ans